Detachable blade propeller



May 9, 1961 Filed April 5, 1956 H. R. UHRICH ET AL DETACHABLE BLADE PROPELLER 4 Sheets-Sheet 1 IN VEN TORS HAROLD RUHR/C Dfcsnszo,

BY .5. MORGAN mm CwPA/vr A/vn J05 E. THOMAS.

ATTOKNE Y y 1951 H. R. UHRICH ETAL 2,983,320

DETACHABLE BLADE PROPELLER Filed April 3, 1956 4 Sheets-Sheet 2 E 20 LL.

INVENTORS HARo LD R. l/HRIcH PE'CEASAD,

5} M kfAu J M/nq (an/1AM? Amado: E. 77444145.

y 1961 H. R. UHRICH ETAL 2,983,320

DETACHABLE BLADE PROPELLER Filed April 5, 1956 4 Sheets-Sheet 3 y 1961 H. R. UHRICH ET AL 2,983,320

DETACHABLE BLADE PROPELLER Filed April 3, 1956 4 Sheets-Sheet 4 INVENTORS #42040 kJ/HE/c/l Den-Assn,

) .i MORGAN MITH renmwr Alva Jo: E. 7waMAs.

united States Paten DETACHABLE BLADE PROPELLER Harold R. Uhrich, deceased late of York, Pa., by Elsie- F. Uhrich, administratrix, and-Joe 'E. Thomas, both of York, Pa.; said Thomas assignor, by mesne assignments, to Allis-Chalmers-Manufacturing Company, Milwaukee, Wis., a corporation of Delaware Filed Apr. 3, 1956, Ser. No. 578,557 (Filed under Rule 47(b) and as U.S.C. r18

11 Claims. c1. 170-16058 This invention relates-to improvements in propellersand, more particularly, to propellers in which the blades are detachably connected to the hub. Still further, butwithout restriction thereto, the improvements afforded by the invention are admirably adapted for use in propellers in which the blades are variably adjustable in pitch relative to the hub. Also, although the principles of the invention are well suited for use in propellers of marinetype, said principles likewise may be incorporated in impellers used in pumps, for example, particularly where the impellers have detachable blades'or the blades are adjustable relative to the hub, or both.

At present, a number of difierent expedients are used for attaching bladm to the hubs of either propellers or pump impellers of the type now used, including both blades which are adjustable as to pitch, and non-adjustable. There are certain advantages, particularly for manufacturing purposes, in making propellers and impellers with detachable blades. Further, should a single blade be-- come damaged during use, it is only necessary toreplace that blade and this frequently can be done without removing the propeller, for example, from the ship. Large marine propellers for example are costly and'the advantage of being ableto replaceonly a single damaged blade as distinguished from having to repair a'fixed blade; 'ofa propeller or replace the entire propeller, is obvious;

Some of the present means used for connecting detachable blade propellers1 to the hubs therefor include com-. plementary threads on the blade shanksgand socketsof the hub, and direct bolting of flanges formed, forexample,

on each blade-to either a socket or the exterior surface of the propeller hub. The same is true relative to cer-.

The present invention alfordsa construction adapted for I incorporation in eithera propeller or pump impellerwhich has none of the disadvantages referred to above relative to presently, used'constructions of this type. It is the principal object ofthe inventionto provide means for rigidly and may. connecting detachable blades to the hub of a propeller orpuinp impeller, the connecting means, in the preferred embodimentlof theinvention, being op-- era-ble by mechanismfa'ccessible externally of the hubbut which nevertheless affords no impedence to the operation of the propellers. l v l A further object of the invention is to provide mechanism having the" foregoing characteristics but which is compact in size and hence requires a propeller hub of only size, said construction being adaptable with equal facility to propellers or pump impellers having blades thatare only detachable or which also may be Patented May 9, 196 1 tive to the hub which supports them.

Still another object of the invention is to include mechanism by which not only may the bladm be attached to and disconnected from the propeller hub by means operable entirely from the exterior of the hub but said mechanism also operates to .insure positive disconnection of the connecting means from its operative position relative to the blades,'thereby to free the blades for separation from the hub.

Details of the foregoing objects and of the invention, as well as other objects thereof, are set forth in' the following specification and illustrated in the accompanying drawings comprising a part thereof.

In the drawings:

. Fig. 1 is a perspective view of an exemplary propeller embodying the principles of the present invention.

Fig. 2 is a longitudinal sectional view of the propeller shown in Fig. 1 but illustrated on a larger scale, one of the'blade receiving socket members being shown insec- 1 tion in this figure, while another of said socket members is not sectioned.

Fig. 3 is a sectional view of the propeller shown in- Fig. 2, taken on the line 3-3 of Fig. 2.

,Fig. 4 is a transverse, fragmentary sectional view of the socket means for mounting the blades in the hub of the exemplary mechanism illustrated in the foregoing figures but shown on a larger scale than in any of said figures.

For purposes of facilitating the illustration of the principles of the present invention with a minimum of description and illustrations, a marine-type propeller of the variable pitch blade type has been selected as a specific example. Such propeller is shown in perspective view in Fig. 1. However, it isto be understood that the principles of the invention may be used with equal facility in a propeller or pump impeller. either of the variable pitch blade type or detachable, non-adjustable blade type. or otherwise. Hence, the present illustrations are not to be considered restrictive in any way as to the field of application of the invention since such illustrations primarily serve in an explanatory capacity.

, Referring to Fig. 1, the fragmentary outer end of a propeller shaft 10 is shown, this being secured by conventional means such as bolts 12 to the forward end of the hub casing 14. A plurality of blades '16 extend substantially radially from the hub casing 14 and, in the specific embodiment illustrated herein, said blades simultaneously are variable in pitch relative to the hub casing by mechanism to 'be described hereinafter.

In the construction illustrated herein for purposes of describing one preferred embodiment of the invention,

' the hub casing 14 is hollow for purposes of accommodating means by which the blades-are connected to the hub as well as meansoperable to vary the pitch of the blades. For example, suitable means such as an annular flange 18 is provided for each blade. Viewed in the direction of the axis of the propeller shaft 10, the annular flanges 18 are spaced equally apart circumferentially around the interior of hub 14. Said flanges comprise fixed bearings which preferably have suitable bearing surfaces such as bronze metal 20 affixed to the inner diameter surface as well as on the inner and outer surfaces of the bearing flanges 18 which are parallel to each other. 1

Each of the annular flanges 18 supports a socket memberor element 22 which has a preferably cylindrical socket 24 therein and a fixed annular flange 26 adjacent the outer end of the socket. The flange 26 of each socket element slidably engages the outer bearing coating 20 of the supporting annular flange 18 and a transverselysplit removable flange 28 surrounds the socket element 22 and slidably engages the inner bearing surface 20 of the an- Tnular flange 18. Split ring members 30 are received in a suitable annular groove '32 in the socket element 22 for purposes of holding the removable flange 28 in operative position. The removable flange 28 is held against relative rotation with socket element 22 by key 34.

A blade adjusting shaft 36 extends axially throughpropeller shaft into the hub casing 14 and a cross-head 38 is fixed to the outer end thereof. Each of the removable flanges 28 also serve as a crank ring and have suitable projections supporting a crank pin 40 shown best in dotted lines in Fig. 2. A connecting rod 42 is pivotally connected between each crank pin 40 and the cross-head 38, whereby, as the adjusting shaft 37 is reciprocated longitudinally in either direction relative to the propeller shaft 10, all of the socket elements 22 will be rotated about the axes thereof simultaneously in the same direction. As is clear from Fig. 2, coupling members 44 are fixed to the crosshead 38 and are pivotally'connected to the rearward end of each of the connecting rods 42.

Each of thesocket elements. 22 receive the shank 46 of one of the blades 16. As has been stated hereinabove, one of the principal objects of the invention is to provide means for detachably connecting blades to the hub of a propeller and, more particularly to provide actuating means for the connecting mechanism which may be operated externally of the blade and hub when it is desired to connect a blade to the hub or detach it therefrom.

One embodiment of preferred connecting mechanism is illustrated in the drawings and, essentially, comprises two supplementary connecting means having different but related functions. One of these connecting means is for purposes of resisting relative movement between the propeller blades and; the socket members 22 in a direction axially of the blades. The mechanism for accomplishing this comprises an annular, interrupted flange 48 formed on the inner end of each socket element 22, while a complementary annular interrupted flange 50 is formed on the inner end of shank 48 of each blade. The interrupted flanges 43. and 50 of the socket elements and blade shanks function similarly to bayonet-slot connecting means, whereby the blade shank 46 initially is inserted axially into the socket 24 of the socketielement 22 and, afterthei projecting. portions of flange 50 have passed between the projecting portions of flange 48,. the blade is then rotated about its axis a sufiicient distance to place the projecting portions of each of said interrupted flanges in opposition to each other, whereby relative axial movement between the socket element and blades is prevented.

Preferably, the inner end of the socket element 22 is provided with a sealing cover 52 which may be bolted or otherwise securely attached over the opening in the inner end of the socket element. Said cover prevents the leakage of any hydraulic fluid from within the hub casing 14 into the sockets of the socket elements, or the passage of any extraneous external material such as water into the interior of the hub casing.

In the exemplary embodiment of the invention illustrated and described herein, each bladeis provided with a flange-like, annular blade palm 54 which preferably is received within a complementary circular cavity 56 formed in the hub casing 14. After the blade 16 has been connected to the socket element 22 by means of the to abut the keying pins 58 and, preferably, the plugs 60 i are threaded into the palm sufliciently that they tend to move the blade shank 46'slightly outwardly'relative to the socket elements so as to place the abutting members of the interrupted flanges48 and 50 infirm engagement with;

the.

each other and thereby prevent any further axial movement of the blades relative to the socket elements 22 in the propeller.

If desired, a soft nose element 62 may be provided on the inner end of each locking plug 60. Due to the bending of the blade shank during operation from the thrust load the lockingiplug60 at'least on therforward' sidesof loads placed against the same, there is atendency to overwhich engages a complementary cylindrical surface 68 on the inner end of the shank 46. The outer surface of ring 64 is tapered. as is clearly shown in Figs; 2 through 4. Said taper is complementary to and cooperates with a similarly tapered surface on the interior of clamping ring.

66, the angle of said taper preferably being greater relative to the axis of the shank than a second tapered surface also formed on ring 66,. said latter tapered surface being complementary to conical surface 72 formed on the shank 46 of each blade between the cylindrical portion 68 thereof and the palm 54.

The principal purpose of the clamping rings 64 and 66 is to engage longitudinally spaced portions of the shank of the blade preferably respectively adjacent the outer and inner ends of the socket '24 in the socket element 22.

Such arrangementprovides an eflicient'bracing effect between the shank 46 of theblade'and the socket element 22. Both of these rings are split at one portion so as to permit limited expansion and contraction thereof in order that the desired clamping" function of the rings, which takes place in a wedging. manner, may be effected suitably, by means now to be described.

The. clamping function. of the rings 64 and 66 is achieved by means of a plurality of circumferentially spaced actuating members comprising bolts or threaded rods 74. The inner ends of the bolts or threaded rods 74 are threaded into suitable openings formed in the inner clamping ring 64 as is clearlyshown in- Figs. 2 and 4, while wherethe members 74 are bolts, the head ends 76 thereof are disposed near the outer surface of the blade palm 54 as is clearly shown in Fig. 4 particularly, said bolt heads engaging suitable annular shoulders formed in the blade palm 54; These heads 76 may be of any suitabletype such as socketedso as to beoperable by appropriate wrenches of the Allen type, or otherwise. 1

The clamping rings 64 and 66 are held preferably against rotation relative to the blade shank 46 by suitable means such as pins 78 and 80 which fit into axially ex- 64 and 66 as shown in said figure. When final clamping of the blade shank 64 in each socket element 2 2 is to be made, the bolts or threaded rods'74' are progressively and successively tightened from the exterior of thepropeller so as to move the. inner clamping ring, 64 axially outward,'thereby slidably moving the outer clamping ring 66 outwardly relative to the socket 24'until' the tapered surface 70 thereon is wedged as'firmly as possible against the tapered surface 72 on the shank 46. The split in the ring 66 is sufficiently wide 'topermit said ring. to be contracted suitably to allow as much wedging action as is necessary to take place in the mannerdescribedl Itwill be seen from Fig. 4 particularlythat the outer surface of the outer clamping ring66 preferablyis cylindrical and therefore complementary to, thepi'nner walls 'of' the socket 24, saidouter tsurface of ringe66 b'eing relieved intermediately of. the opposite ends thereof, if desired; as showniin Fig.4. Sta-engagement. between the;

5 wallszof socket '24 andthe puten surfaces of the (outer; end portion, of ring 66 will: move the opposite tapered; surface of saidring against. the tapered shank surface 72; and effect the fdesiredwedging actionbetween the-taperedsurfaces 70 and 72 of the ring and" blade shank, as best' seen-in Fig. 4, wherebyv what may be termed the outer portion of the shank 64"is:=firmly andwedgingly clamped within the socket element 22.

Simultaneously with the clamping and connectingfunc tion just described relative to" the-tapered surface 70-,of, clamping ring 66, the other. tapered surface thereon which is complementary to the tapered surface on inner clamping rings 64 causes said inner ring 64 to be wedgingly and firmly contracted into clamping engagement with the cylindrical surface 68 of shank 46 which is adjacent the.

inner end of said shankwhich is longitudinally spaced from the portion of theshank: engaged by o ring 66. Hence, when the actuating members 74 for the connecting'means, comprising clamping rings '64 and 6 8, have beenthreaded into inner clamping ring 64 as far as possible, the shank '46 ofeach blade is firmly and Wedgingly clamped within the socket element 22 at longitudinally spaced portions of saidsha-nk and socket element,-'where-' by the blade connecting means is capable of successfully;

resisting vibrations and other operational stresses imposedupon the blades during use thereof; Further, in the pre ferred embodiment of the invention, locking plugs 82 are threaded into suitable sockets communicating with the outer ends of those which receive the bolts or threaded.

rods 74 so as to engage the outer ends of the latter and prevent movement thereof in unthreading direction relative to the inner clamping ring 64.

As an alternative to the use of bolts 74 which have heads 76 on the outer ends thereof engageable with annular shoulders in theblade palm 54, rods which are threaded on the inner ends thereof may be substituted for the bolts 74 and the inner ends of said rods are threaded through the inner clamping ring 164 so as token-- gage the bottom surface of the socket 24,.whereby'saidrods act as jack screwsto force theinner clampingring- 64 away from the bottom of the socket element 22'. Un-

der these circumstances; the outer ends of the rods need not have a bolt head thereon but should be provided with.

some suitable means such as sockets to beengaged by an Allen wrench or the like for purposes of rotating the rods;

However, under these circumstances, locking means such.

as plugs 82 preferably should be used to engage the ends of the threaded rods. No specific illustration of these.

rods is made due to a close resemblance thereof to the,

bolts 74. v n n From the foregoing, it will be seen that the connection of the blades 1-6 to the socket elements 72 is achieved by connecting means which are operable from the ex-' terior of the blades and 'hub of the propeller, whereby.

under normal condition of operations, it is not necessary to enter'the-hub casing 14 for any purposes regarding the connection or disconnectionof the blades relative to the hub. When, for any reason, it is desired to disconnect.

one of the blades from thehub, it is only necessary .to remove the locking plugs 60 and '82 from the hub; rotate the bolts or threaded rods 74 in unclamping direction,

which initially results in the bolts being threaded'outward.

relative to ring 64 since the clamping engagements between the rings 64 and 66'and the bladeshank and socket From the foregoing, it will'beseen that the. present invention provides connecting means for detachably' still are tight; and then tapping .the outer ends of the bolts ring 64 in-the outer clamping ring; 64 being. withdrawn from wedging engagement between .the. :socket wall 24 and the conical surface-72 0a 46.of.th'e blade. This thereby releases the blade and socket'element. from -all influenceby'the, clamping, rings and 66. Upon 'r'e-Q moval of the lockingpin -58,' theblade' then maybe rotated axially so as" to effect disengagement of the interruptedlockingrings 48 and 50 with eachother, whereupon theflblade may. be removed entirelyfrom the socket element22." n

Inaddition to thesealing effect afiorded by cover 52 of the innerend ofsocket element 22, further sealing members preferably. are provided such as afixed'annular sealiiigl'shoel 8 8 which is 'dispos'edin a suitable recess in' hubcasin'g"1'4fand slidably wipes against the inner sur-' 'face of blade palm 54 when the blades are adjusted in pitch. Still further, a compressible annular sealing ring may be" disposed between the. outer end of the wall defining socket 24 and the shank 46- adjacent the outer extremity of the tapered surface 70 thereon.

clamping the shanks of blades in. sockets'or socket elementsQinth'ehubs of propellers or impellers, said con necting} means bein'goperable by.means arranged to be actuated from the exterior' of the blades and hub of'the propelleror impeller. Saidconnecting means not only withstands bending'moments between the blade shanks and thesocket elements to which they are connected when the invention is applied to a propeller or impeller of the variable pitch blade type, but any suchbending moments also'are'withstood between .the blade shanks and thehub' of the propeller or impeller in the event" sockets to receive such shanks directly are providedin the hub member. The connecting means also include. elemerits. which prevent relative movement between the blades and sockets of the hub in a directionv axially of the blades. Further, the connecting means also are arrangedlpreferably. to engage the shank of the blade ad-.

jacent'oppositejends thereof so, as to'afiord as efficient resistance'to bending moments as possible. Maximum efiiciency of connection also. is provided with a minimum of space requiredjin the hub. Further,- all elements employed in: the structure comprising the invention may be made from any'suitable material dictated by the medium within which the propelleror impel'leris to be used. Where in the appended claims, the term propeller. is used, it is to be'understood that said term is used in the generic sense applying equally to both pro- 50' pellers and impellers for pumps and the like;

While the invention has been shown and described in its several preferred embodiments, and has included cer-* tain .details, it should be understood that the invention is not to be limited to theprecise details herein illushated and described since'the same may be carried out in other ways falling within the scope ofthe invention a'sclaimed.

We claim: I 1. A propeller comprising in combination, a hub hav- 1 ing substantially cylindrical radially extending sockets ex-,

tending substantially radiallythereinto, bladesieach having a shank thereon received respectively withinsaidsockets, said shanks being tapered, a plurality of clamp-'- ingrings in each socket having complementary inter-v engaging tapered surfaees'and engageable with said shanks I:

at longitudinally spaced positions,andmeans operable to move said clamping rings into firm clamping engage-.

ment with said. shanks and the interior surfaces. of said socketsfso asto connect said. blades firmly to said hub.. Y

2. A propellercomprising in combination, a hub having sockets extending thereinto at spaced locationsin said hub, blades .having shanks extending respectively into said; sockets, connecting members 1 including; arplura'lity;

of tapered wedging means interengaging each other within each socket between the end of the shank of the blade within the socket and'the interior of the socket andoperable firmly to clamp said shanks within said sockets, and operating means engageable with said tapered wedging means and operable from the exterior of said hub to move said wedging means into firmengagement with said shanks and sockets.

3. A propeller comprising in combination, a hub having sockets thereim'blades having shanks extending into said sockets, connecting means on the inner ends of said shanks and. interior of said sockets comprising radially extending intereng'age'able' interrupted flanges operable to interlock by fractional rotation to prevent relative axial movement between said blades and sockets, and

additional connecting means comprising a plurality of annular tapered wedging means surrounding each shank within each socket and respectively'clampingly engagingeach shank at longitudinally spaced positions thereon within said sockets, whereby said blades are firmly clamped to said hub to resist loosening in said sockets by vibration and operational stresses.

4. A propeller comprising in combination, 'a hub having substantially cylindrical sockets therein, blades having shanks extending into said sockets, connecting means on said shanks and within said sockets comprising interengageable interrupted flanges adjacent the, inner ends of said shanks and operable to prevent relative axial movement between said blades and sockets, additional connecting means comprising a plurality of annular tapered wedging means surrounding each shank within each socket and respectively cl-ampingly engaging each' shank at longitudinally spaced portions thereonwithin said sockets, and means interconnected within said sockets to at least one of said connecting means and operable from the exterior of said hub to move said additional connecting means into firm contact with said shanks of said blades.

5. A propeller comprising in combination, a hub having sockets extending substantially radially thereinto' atsame into firm clamping engagement longitudinally spaced portions of said shanks.

6. A propeller comprising in combination, a hub having sockets extending substantially radially. thereinto at spaced locations in said hub, blades having shanks provided with tapered and cylindrical portions thereon received within said sockets, a set of rings surrounding each shank within the socket therefor, one ring. of each set having two tapered portions and one of said tapered portions being complementary to the tapered portion of said shank and engaging the same, the other ring having a tapered portion complementary to the other tapered portion of said one ring and a cylindrical portion engaging the cylindrical portion of said shank, and means engageable with one of said rings and operable to move the same and the other ring into firm clamping engagement with longitudinally spaced portions of said shanks, one of said portions being said cylindrical portion.

7. A propeller comprising in combination, a hub having sockets extending substantially radially thereinto at locations spaced around said hub, blades having tapered shanks extending respectively into said sockets, split rings tions being complementary to the taper of said shankand engaging the same, the other-ring having a tapered portion complementary to the other tapered portion of said one ring and engageable therewith, and bolt-like means threadably engaging one of said rings and operrings having two tapered portions and one of said tapered portions being complementary to the taper of said shank and engaging the same, the other ring having a tapered-portion complementary to the other tapered portion of said one ring and engageable therewith, and boltlike means threadably engaging said other ring and operable thereby to move said one ring into wedging clampingengagement between said socket and shank and said one ring simultaneously urges said other ring into wedging clamping engagement with said shank at a position thereon longitudinally spaced from the portion of said shank engaged by said one ring.

9. A propeller comprising in combination, a hub having sockets extending substantially radially thereinto, blades each having a tapered shank thereon received respectively within said sockets, a set of clamping rings respectively engageable with each of said shanks at longitudinally spaced positions, one ring of each set being engageable with the other ring of said set to move the latter into engagement with said tapered shank to wedgingly clamp the same within the socket therefor, and means operable to move said one clamping ring of each set into engagement with the other ring of each set and also to cause said one clamping ring of each set to be moved into clamping engagement with said shank to clamp said shanks efiectively within said sockets.-

10. A propeller comprising in combination, a hub having spaced sockets extending substantially radially thereinto, blades each having a tapered shank thereon received respectively within said sockets, connecting means comprising tapered wedging means engageable with the tapers on said shanks to clamp said shanks firmly within said sockets, actuating means operable to move said connecting means into firm clamping engagement with said shanks, and means within said socket and movable in an axial direction relative to said sockets and engageable with said connecting means and operable to move the same axially of said sockets to relieve said shanks from clamping engagement by said connecting means when said blades are to be removed from said sockets.

11. A propeller comprising in combination, a hub having sockets extending substantially radially thereinto, blades each having a shank thereon received respectively within said sockets, clamping rings having portions respectively engageable with said shanks at longitudinally spaced positions and also interengageable with the interior of said sockets to clamp said shanks firmly within said sockets, means operable to move said clamping rings into said clamping engagement with said shanks, and means on said rings movable axially into coengagement to free said rings from clamping engagement with said shanks when said blades are to be removed from said sockets.

References Cited in the file of this patent UNITED STATES PATENTS 1,661,631 Nixon Mar. 6, 1928 1,769,801 McCauley July 1, 1930 2,147,336 Feddenet al Feb; 14, 1939 2,693,243 Strandell et a1.. Nov. 2, 1954 FOREIGN PATENTS 17,355 France Aug. 22, 1913 543,990

Great Britain Mar. 23, 1942 

